Hello,
I think you are scaring the horses
Now the offer has arrived and all wishes and requirements are listed so far. The price is also acceptable so far. But unfortunately the floor plans are missing?! Apparently they will only be released after signing.
By mail? Strange that ....
But – an offer is far from being a contract for work. It will be the case that the offer is used as an annex to the contract for work; incl. floor plans. How else can you be sure what exactly you have bought?
But what are we signing now? In my opinion the offer does not yet constitute a legally binding construction contract, right? Neither payment terms, construction start, nor anything else is clarified. What happens if the offer is accepted but the construction contract does not come about for some reason? Can you then withdraw from the "offer"?
First of all, I find it troubling that you have to ask these questions here in the forum. I would have expected your potential contract partner to sufficiently inform you!
An offer is and remains an offer; it is not signed but becomes part of a contract for work yet to be signed. _Before_ you sign it, however, you should familiarize yourself with the wording of the contract for work; if necessary have it reviewed by a lawyer, if there is a need. Only when you understand everything, offer, service + price are right for you, should you sign
Rhenish greetings